On Thu, May 2, 2013 at 9:09 PM, Tejun Heo <t...@kernel.org> wrote: > Hello, > > On Thu, May 02, 2013 at 07:41:39PM -0700, Colin Cross wrote: >> On Thu, May 2, 2013 at 7:16 PM, Colin Cross <ccr...@android.com> wrote: >> > This sounds the same as what ended up getting reverted in >> > https://lkml.org/lkml/2013/3/4/221 >> > I can add the WARN_ON_ONCE to all my new calls, and leave them out of >> > existing calls, but that seems a little odd, and will be redundant if >> > the lockdep call in try_to_freeze goes back in in 3.11. Do you still >> > want it in the new apis? > ... >> I could also put the lockdep check that was reveted back into >> try_to_freeze(), and add a freezable_schedule_unsafe() that skips it >> for use in the known-unsafe users in nfs, with a big comment not to >> add new users of it. > > Oh yeah, that sounds like a good idea, and as for the non-ugly > variants, at least in the mid/long term, I think it'd be best to add > the lockdep annotation to try_to_freeze() with > __try_to_freeze_unsafe_youre_gonna_burn_in_hell_if_you_use_this() for > the existing users which should be gradually converted, but if that's > too burdensome, adding warnings to the wrappers should do for now, I > guess. > > And I *hope* the lockdep annotation is stricter than what was added > before. I think it better be "no lock ever should be held at this > point" rather than "consider this a big lock".
The previous patch (6aa9707099c4b25700940eb3d016f16c4434360d in Linus' tree) already required that no locks be held, it wasn't using a lock annotation. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/